摘要 |
It is described a method for dynamically optimizing the signal-to-noise ratio of attenuation data related to two different X-ray energies for reconstructing an image of an object under examination. The method comprises (a) estimating the thickness and the material composition of the object at a plurality of different projection angles, (b) for each of the various projection angles calculating for a variety of combinations of different first and second X-ray energies a corresponding common signal-to-noise ratio, (c) for each of the various projection angles choosing the first and the second X-ray energy causing the maximum corresponding common signal-to-noise ratio, and (d) for each of the various projection angles acquiring X-ray attenuation data of the object whereby the two X-ray energies are the X-ray energies causing a maximum signal-to-noise ratio assigned to the respective projection angle. |